Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Takashi Hosoya; Nele Sophie Zwirchmayr; Karl Michael Klinger; Heidemarie Reiter; Martin Spitzbart; Thomas Dietz; Klaus Eibinger; Wolfgang Kreiner; Arnulf Kai Mahler; Heribert Winter; Thomas Röder; Antje Potthast; Thomas Elder; Thomas Rosenau
    Date: 2018
    Source: Cellulose
    Publication Series: Scientific Journal (JRNL)
    Station: Southern Research Station
    PDF: Download Publication  (1.0 MB)

    Description

    5,8-Dihydroxy-[1,4]-naphthoquinone (DHNQ) is one of the key chromophores occurring in all types of aged cellulosics. This study investigates the degradation of DHNQ by chlorine dioxide at moderately acidic (pH 3) conditions, corresponding to the conditions of industrial bleaching (‘‘D stage’’). The degradation involves three major pathways. As initial reaction, a hydrogen transfer from DHNQ to chlorine dioxide via a PCET mechanism occurs to form a radical DHNQ and chlorous acid. DHNQ is then attacked by water to give a pentahydroxynaphthalene radical PHN that is stabilized by strong delocalization of the non-paired electron into its aromatic ring. PHN immediately disproportionates to give the observable intermediate 1,2,4,5,8-pentahydroxynapththalene (I), which was comprehensively confirmed by NMR and MS (path A). In the presence of excess ClO2, I is immediately further oxidized into acetic acid, glycolic acid, oxalic acid and CO2 as the final, stable, and noncolored products (path C). In the absence of excess ClO2, elimination of water from I regenerates DHNQ (path B), so that at roughly equimolar DHNQ/ClO2 ratios ClO2 is fully consumed while a major part of DHNQ is recovered. To avoid such DHNQ ‘‘recycling’’ under ClO2 consumption—and to completely degrade DHNQ to colorless degradation products instead—ClO2 must be applied in at least fivefold molar excess relative to DHNQ.

    Publication Notes

    • You may send email to pubrequest@fs.fed.us to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

    Citation

    Hosoya, Takashi; Zwirchmayr, Nele Sophie; Klinger, Karl Michael; Reiter, Heidemarie; Spitzbart, Martin; Dietz, Thomas; Eibinger, Klaus; Kreiner, Wolfgang; Mahler, Arnulf Kai; Winter, Heribert; Röder, Thomas; Potthast, Antje; Elder, Thomas; Rosenau, Thomas. 2018. Chromophores in cellulosics, XVIII. Degradation of the cellulosic key chromophore 5,8-dihydroxy-[1,4]-naphthoquinone under conditions of chlorine dioxide pulp bleaching: a combined experimental and theoretical study. Cellulose. 25(9): 4941-4954. https://doi.org/10.1007/s10570-018-1912-2.

    Cited

    Google Scholar

    Keywords

    Cellulose, Pulp bleaching, Chromophores, Brightness, Brightness reversion, Yellowing, 5, 8-dihydroxy-[1, 4]-naphthoquinone, Chlorine dioxide, Ab initio calculations, Density functional theory (DFT)

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/56935